Systems and methods for the treatment of pain through neural fiber stimulation

Abstract

Embodiments of the present invention provide systems and methods for the treatment of pain through activation of select neural fibers. The neural fibers may comprise one or more afferent neural fibers and/or one or more efferent neural fibers. If afferent fibers are stimulated, alone or in combination with efferent fibers, a therapeutically effective amount of electrical stimulation is applied to activate afferent pathways in a manner approximating natural afferent activity. The afferent fibers may be associated with primary receptors of muscle spindles, golgi tendon organs, secondary receptors of muscle spindles, joint receptors, touch receptors, and other types of mechanoreceptors and/or proprioceptors. If efferent fibers are stimulated, alone or in combination with afferent fibers, a therapeutically effective amount of electrical stimulation is applied to activate intrafusal and/or extrafusal muscle fibers, which results in an indirect activation of afferent fibers associated therewith.

Having thus described the invention, we claim: 
     
       1. An electrical stimulation system comprising:
 a percutaneous lead consisting of a single contact electrode, wherein the single contact electrode is configured to be inserted in-vivo a therapeutically effective distance from a target afferent nerve fiber; and 
 an external electrical stimulator operatively coupled with the single contact electrode, wherein the external electrical stimulator is configured to provide electrical stimulation through the single contact electrode to the target afferent nerve fiber, wherein the external electrical stimulation comprises a waveform configured to generate an action potential in the target afferent nerve fiber while avoiding generation of unwanted responses in non-target nerve fibers. 
 
     
     
       2. The electrical stimulation system of  claim 1 , wherein the single contact electrode has a surface area of approximately 20 mm 2 . 
     
     
       3. The electrical stimulation system of  claim 1 , wherein the electrical stimulation comprises a current configured to generate the action potential in the target afferent nerve fiber while avoiding generation of unwanted responses in non-target nerve fibers. 
     
     
       4. The electrical stimulation system of  claim 1 , wherein the electrical stimulation comprises a voltage configured to generate the action potential in the target afferent nerve fiber while avoiding generation of unwanted responses in non-target nerve fibers. 
     
     
       5. An electrical stimulation system comprising:
 a percutaneous lead consisting of a single contact electrode coupled with the percutaneous lead, wherein the single contact electrode is configured to be positioned at a therapeutically effective distance from a target Type I or Type Ib afferent nerve fiber; and 
 an external electrical stimulator coupled with the percutaneous lead, wherein the electrical stimulator is configured to deliver electrical stimulation through the single contact electrode to the target Type I or Type Ib afferent nerve fiber and wherein a waveform of the electrical stimulation is configured to generate an action potential in the target Type I or Type Ib afferent nerve fiber while avoiding generation of unwanted responses in non-target Type III and Type IV afferent nerve fibers to reduce a perception of pain. 
 
     
     
       6. The electrical stimulation system of  claim 5 , wherein the single contact electrode has a surface area of approximately 20 mm 2 . 
     
     
       7. The electrical stimulation system of  claim 5 , wherein a current of the electrical stimulation is configured to generate the action potential in the target Type I or Type Ib afferent nerve fiber while avoiding generation of unwanted responses in non-target Type III and Type IV afferent nerve fibers. 
     
     
       8. The electrical stimulation system of  claim 5 , wherein a voltage of the electrical stimulation is configured to generate the action potential in the target Type I or Type Ib afferent nerve fiber while avoiding generation of unwanted responses in non-target Type III and Type IV afferent nerve fibers. 
     
     
       9. An electrical stimulation system comprising:
 a percutaneous lead consisting of a single contact electrode, the single contact electrode configured to be inserted into a human body; and 
 an electrical stimulator operatively coupled with the lead, the electrical stimulator configured to deliver electrical stimulation to at least one of Type Ia and Ib target afferent nerve fibers wherein the electrical stimulation comprises a waveform configured to generate an action potential in the at least one of Type Ia and Ib target afferent nerve fibers while avoiding generation of action potentials in non-target Type III and IV nerve fibers to reduce a perception of pain by the human body. 
 
     
     
       10. The electrical stimulation system of  claim 9 , wherein the electrical stimulation comprises a waveform and wherein the waveform is configured to generate the action potential in the at least one of Type Ia and Ib target afferent nerve fibers while avoiding generation of action potentials in non-target Type III and IV nerve fibers. 
     
     
       11. The electrical stimulation system of  claim 9 , wherein the electrical stimulation comprises a current and wherein the current is configured to generate the action potential in the at least one of Type Ia and Ib target afferent nerve fibers while avoiding generation of action potentials in non-target Type III and IV nerve fibers. 
     
     
       12. The electrical stimulation system of  claim 9 , wherein the electrical stimulation comprises a voltage and wherein the voltage is configured to generate the action potential in the at least one of Type Ia and Ib target afferent nerve fibers while avoiding generation of action potentials in non-target Type III and IV nerve fibers.